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Diffstat (limited to 'package/kernel/mac80211/patches/subsys/312-net-fq_impl-do-not-maintain-a-backlog-sorted-list-of.patch')
-rw-r--r--package/kernel/mac80211/patches/subsys/312-net-fq_impl-do-not-maintain-a-backlog-sorted-list-of.patch317
1 files changed, 0 insertions, 317 deletions
diff --git a/package/kernel/mac80211/patches/subsys/312-net-fq_impl-do-not-maintain-a-backlog-sorted-list-of.patch b/package/kernel/mac80211/patches/subsys/312-net-fq_impl-do-not-maintain-a-backlog-sorted-list-of.patch
deleted file mode 100644
index 2fa2ba41ac..0000000000
--- a/package/kernel/mac80211/patches/subsys/312-net-fq_impl-do-not-maintain-a-backlog-sorted-list-of.patch
+++ /dev/null
@@ -1,317 +0,0 @@
-From: Felix Fietkau <nbd@nbd.name>
-Date: Wed, 25 Nov 2020 18:10:34 +0100
-Subject: [PATCH] net/fq_impl: do not maintain a backlog-sorted list of
- flows
-
-A sorted flow list is only needed to drop packets in the biggest flow when
-hitting the overmemory condition.
-By scanning flows only when needed, we can avoid paying the cost of
-maintaining the list under normal conditions
-In order to avoid scanning lots of empty flows and touching too many cold
-cache lines, a bitmap of flows with backlog is maintained
-
-Signed-off-by: Felix Fietkau <nbd@nbd.name>
----
-
---- a/include/net/fq.h
-+++ b/include/net/fq.h
-@@ -19,8 +19,6 @@ struct fq_tin;
- * @flowchain: can be linked to fq_tin's new_flows or old_flows. Used for DRR++
- * (deficit round robin) based round robin queuing similar to the one
- * found in net/sched/sch_fq_codel.c
-- * @backlogchain: can be linked to other fq_flow and fq. Used to keep track of
-- * fat flows and efficient head-dropping if packet limit is reached
- * @queue: sk_buff queue to hold packets
- * @backlog: number of bytes pending in the queue. The number of packets can be
- * found in @queue.qlen
-@@ -29,7 +27,6 @@ struct fq_tin;
- struct fq_flow {
- struct fq_tin *tin;
- struct list_head flowchain;
-- struct list_head backlogchain;
- struct sk_buff_head queue;
- u32 backlog;
- int deficit;
-@@ -47,6 +44,7 @@ struct fq_flow {
- struct fq_tin {
- struct list_head new_flows;
- struct list_head old_flows;
-+ struct list_head tin_list;
- struct fq_flow default_flow;
- u32 backlog_bytes;
- u32 backlog_packets;
-@@ -60,14 +58,14 @@ struct fq_tin {
- /**
- * struct fq - main container for fair queuing purposes
- *
-- * @backlogs: linked to fq_flows. Used to maintain fat flows for efficient
-- * head-dropping when @backlog reaches @limit
- * @limit: max number of packets that can be queued across all flows
- * @backlog: number of packets queued across all flows
- */
- struct fq {
- struct fq_flow *flows;
-- struct list_head backlogs;
-+ unsigned long *flows_bitmap;
-+
-+ struct list_head tin_backlog;
- spinlock_t lock;
- u32 flows_cnt;
- u32 limit;
---- a/include/net/fq_impl.h
-+++ b/include/net/fq_impl.h
-@@ -17,12 +17,24 @@ __fq_adjust_removal(struct fq *fq, struc
- unsigned int bytes, unsigned int truesize)
- {
- struct fq_tin *tin = flow->tin;
-+ int idx;
-
- tin->backlog_bytes -= bytes;
- tin->backlog_packets -= packets;
- flow->backlog -= bytes;
- fq->backlog -= packets;
- fq->memory_usage -= truesize;
-+
-+ if (flow->backlog)
-+ return;
-+
-+ if (flow == &tin->default_flow) {
-+ list_del_init(&tin->tin_list);
-+ return;
-+ }
-+
-+ idx = flow - fq->flows;
-+ __clear_bit(idx, fq->flows_bitmap);
- }
-
- static void fq_adjust_removal(struct fq *fq,
-@@ -32,24 +44,6 @@ static void fq_adjust_removal(struct fq
- __fq_adjust_removal(fq, flow, 1, skb->len, skb->truesize);
- }
-
--static void fq_rejigger_backlog(struct fq *fq, struct fq_flow *flow)
--{
-- struct fq_flow *i;
--
-- if (flow->backlog == 0) {
-- list_del_init(&flow->backlogchain);
-- } else {
-- i = flow;
--
-- list_for_each_entry_continue(i, &fq->backlogs, backlogchain)
-- if (i->backlog < flow->backlog)
-- break;
--
-- list_move_tail(&flow->backlogchain,
-- &i->backlogchain);
-- }
--}
--
- static struct sk_buff *fq_flow_dequeue(struct fq *fq,
- struct fq_flow *flow)
- {
-@@ -62,7 +56,6 @@ static struct sk_buff *fq_flow_dequeue(s
- return NULL;
-
- fq_adjust_removal(fq, flow, skb);
-- fq_rejigger_backlog(fq, flow);
-
- return skb;
- }
-@@ -90,7 +83,6 @@ static int fq_flow_drop(struct fq *fq, s
- } while (packets < pending);
-
- __fq_adjust_removal(fq, flow, packets, bytes, truesize);
-- fq_rejigger_backlog(fq, flow);
-
- return packets;
- }
-@@ -170,22 +162,36 @@ static struct fq_flow *fq_flow_classify(
- return flow;
- }
-
--static void fq_recalc_backlog(struct fq *fq,
-- struct fq_tin *tin,
-- struct fq_flow *flow)
--{
-- struct fq_flow *i;
--
-- if (list_empty(&flow->backlogchain))
-- list_add_tail(&flow->backlogchain, &fq->backlogs);
--
-- i = flow;
-- list_for_each_entry_continue_reverse(i, &fq->backlogs,
-- backlogchain)
-- if (i->backlog > flow->backlog)
-- break;
-+static struct fq_flow *fq_find_fattest_flow(struct fq *fq)
-+{
-+ struct fq_tin *tin;
-+ struct fq_flow *flow = NULL;
-+ u32 len = 0;
-+ int i;
-+
-+ for_each_set_bit(i, fq->flows_bitmap, fq->flows_cnt) {
-+ struct fq_flow *cur = &fq->flows[i];
-+ unsigned int cur_len;
-+
-+ cur_len = cur->backlog;
-+ if (cur_len <= len)
-+ continue;
-+
-+ flow = cur;
-+ len = cur_len;
-+ }
-
-- list_move(&flow->backlogchain, &i->backlogchain);
-+ list_for_each_entry(tin, &fq->tin_backlog, tin_list) {
-+ unsigned int cur_len = tin->default_flow.backlog;
-+
-+ if (cur_len <= len)
-+ continue;
-+
-+ flow = &tin->default_flow;
-+ len = cur_len;
-+ }
-+
-+ return flow;
- }
-
- static void fq_tin_enqueue(struct fq *fq,
-@@ -200,6 +206,13 @@ static void fq_tin_enqueue(struct fq *fq
-
- flow = fq_flow_classify(fq, tin, idx, skb);
-
-+ if (!flow->backlog) {
-+ if (flow != &tin->default_flow)
-+ __set_bit(idx, fq->flows_bitmap);
-+ else if (list_empty(&tin->tin_list))
-+ list_add(&tin->tin_list, &fq->tin_backlog);
-+ }
-+
- flow->tin = tin;
- flow->backlog += skb->len;
- tin->backlog_bytes += skb->len;
-@@ -207,8 +220,6 @@ static void fq_tin_enqueue(struct fq *fq
- fq->memory_usage += skb->truesize;
- fq->backlog++;
-
-- fq_recalc_backlog(fq, tin, flow);
--
- if (list_empty(&flow->flowchain)) {
- flow->deficit = fq->quantum;
- list_add_tail(&flow->flowchain,
-@@ -218,9 +229,7 @@ static void fq_tin_enqueue(struct fq *fq
- __skb_queue_tail(&flow->queue, skb);
- oom = (fq->memory_usage > fq->memory_limit);
- while (fq->backlog > fq->limit || oom) {
-- flow = list_first_entry_or_null(&fq->backlogs,
-- struct fq_flow,
-- backlogchain);
-+ flow = fq_find_fattest_flow(fq);
- if (!flow)
- return;
-
-@@ -255,8 +264,6 @@ static void fq_flow_filter(struct fq *fq
- fq_adjust_removal(fq, flow, skb);
- free_func(fq, tin, flow, skb);
- }
--
-- fq_rejigger_backlog(fq, flow);
- }
-
- static void fq_tin_filter(struct fq *fq,
-@@ -279,16 +286,18 @@ static void fq_flow_reset(struct fq *fq,
- struct fq_flow *flow,
- fq_skb_free_t free_func)
- {
-+ struct fq_tin *tin = flow->tin;
- struct sk_buff *skb;
-
- while ((skb = fq_flow_dequeue(fq, flow)))
-- free_func(fq, flow->tin, flow, skb);
-+ free_func(fq, tin, flow, skb);
-
-- if (!list_empty(&flow->flowchain))
-+ if (!list_empty(&flow->flowchain)) {
- list_del_init(&flow->flowchain);
--
-- if (!list_empty(&flow->backlogchain))
-- list_del_init(&flow->backlogchain);
-+ if (list_empty(&tin->new_flows) &&
-+ list_empty(&tin->old_flows))
-+ list_del_init(&tin->tin_list);
-+ }
-
- flow->tin = NULL;
-
-@@ -314,6 +323,7 @@ static void fq_tin_reset(struct fq *fq,
- fq_flow_reset(fq, flow, free_func);
- }
-
-+ WARN_ON_ONCE(!list_empty(&tin->tin_list));
- WARN_ON_ONCE(tin->backlog_bytes);
- WARN_ON_ONCE(tin->backlog_packets);
- }
-@@ -321,7 +331,6 @@ static void fq_tin_reset(struct fq *fq,
- static void fq_flow_init(struct fq_flow *flow)
- {
- INIT_LIST_HEAD(&flow->flowchain);
-- INIT_LIST_HEAD(&flow->backlogchain);
- __skb_queue_head_init(&flow->queue);
- }
-
-@@ -329,6 +338,7 @@ static void fq_tin_init(struct fq_tin *t
- {
- INIT_LIST_HEAD(&tin->new_flows);
- INIT_LIST_HEAD(&tin->old_flows);
-+ INIT_LIST_HEAD(&tin->tin_list);
- fq_flow_init(&tin->default_flow);
- }
-
-@@ -337,8 +347,8 @@ static int fq_init(struct fq *fq, int fl
- int i;
-
- memset(fq, 0, sizeof(fq[0]));
-- INIT_LIST_HEAD(&fq->backlogs);
- spin_lock_init(&fq->lock);
-+ INIT_LIST_HEAD(&fq->tin_backlog);
- fq->flows_cnt = max_t(u32, flows_cnt, 1);
- fq->quantum = 300;
- fq->limit = 8192;
-@@ -348,6 +358,14 @@ static int fq_init(struct fq *fq, int fl
- if (!fq->flows)
- return -ENOMEM;
-
-+ fq->flows_bitmap = kcalloc(BITS_TO_LONGS(fq->flows_cnt), sizeof(long),
-+ GFP_KERNEL);
-+ if (!fq->flows_bitmap) {
-+ kvfree(fq->flows);
-+ fq->flows = NULL;
-+ return -ENOMEM;
-+ }
-+
- for (i = 0; i < fq->flows_cnt; i++)
- fq_flow_init(&fq->flows[i]);
-
-@@ -364,6 +382,9 @@ static void fq_reset(struct fq *fq,
-
- kvfree(fq->flows);
- fq->flows = NULL;
-+
-+ kfree(fq->flows_bitmap);
-+ fq->flows_bitmap = NULL;
- }
-
- #endif
---- a/net/mac80211/tx.c
-+++ b/net/mac80211/tx.c
-@@ -3335,8 +3335,6 @@ out_recalc:
- if (head->len != orig_len) {
- flow->backlog += head->len - orig_len;
- tin->backlog_bytes += head->len - orig_len;
--
-- fq_recalc_backlog(fq, tin, flow);
- }
- out:
- spin_unlock_bh(&fq->lock);
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-01 00:15:13 +0000